Collapsible storage tanks



Sept. 30, 1958 S. S. WYLLlE COLLAPSIBLE STORAGE TANKS Filed Dec. 11,1956 United States Patent Q COLLAPSIBLE STORAGE TANKS Stuart SpencerWyllie, Cardiff, Wales, assignor to Elliot Equipment Limited, Rhontlda,South Wales, a British Company Application December 11, 1956, Serial No.627,705

4 Claims. (til. 15(31) This invention relates to collapsible storagetanks such as may be employed for storing water intended for use infire-fighting and otherwise.

It is an object of the invention to devise a collapsible storage tankwhich will in use have a high degree of stability so that it may beemployed as, for example, a small swimming pool.

In accordance with the invention there is provided a collapsible storagetank for liquids, wherein an endless inflatable tube is attached by aflexible side wall to the base of the tank, said tube constituting themouth of the tank and being of area smaller than that of the base sothat, when the tank is erected, said wall converges towards said mouth,the arrangement being such that, when liquid is introduced into themouth of the collapsed tank with said tube inflated, the latter floatsupon the liquid and causes the wall to be erected.

For a better understanding of the invention and to show how the same maybe carried into effect, reference will now be made to the accompanyingdrawing which is a perspective view of a collapsible storage tank withpart of the tank removed for the sake of clarity.

Referring now to the drawing, there is shown a tank having a base 1consisting of heavy waterproof fabric of the kind employed for makinginflatable life rafts. The base 1 is composed of a central circularpanel 2 to the periphery of which several radially outwardly extendingsector-shaped panels 3 are joined. The sector-shaped panels 3 are alsoconnected one to the other along their rectilinear radially extendingsides 4 so that a composite, substantially circular base of, forexample, about twelve feet in diameter, is obtained.

Around the periphery of the base 1 there is attached a circularlyextending inflatable base tube 5. The base tube 5 is of such dimensionsthat, when it is inflated, the cross-sectional diameter of the tube isabout fourteen inches, the tube being arranged for inflation to apressure of about one to two pounds per square inch. The base tube 5 isbuilt up from straight tube sections 6 joined end to end. Each tubesection 6 is of length corresponding to the peripheral length of each ofthe sector-shaped panels 3.

A side wall 7 is attached effectively to the base 1 so as to enclose thebase tube 5. The side wall is such that, when held erect, it constitutesan annulus having at the lower side a diameter corresponding to theexternal diameter of the inflated base tube 5, but diminishing indiameter upwardly away from the base tube. The side wall 7 is formed byjoining together a plurality of panels 8. Each panel 8 appropriatelytapers away from its junction with the base tube 5 towards the upper endof the erected side wall, such upper end constituting the mouth of thetank. The side wall at its month end is Patented Sept. 30, 1958connected to an inflatable tube 9 constructed like the base tube 5 froma plurality of straight tube sections 10. The mouth tube 9, however,extends along a circular path of considerably smaller diameter than thatof the base tube 5. The mouth tube 9 may, for example, afford a mouthopening of about eight feet in diameter, and,

the erected tank may stand about four feet high.

In the use of the tank, both the mouth tube 9 and the base tube 5 areinflated through conventional inflation valves (not shown). At this timethe side wall 7 will not be held erect and the mouth tube 9 will liealmost within the base tube 5. Water is now poured over the mouth tube 9so that the water is initially stored between the base 1 and the basetube 5. As the water level rises, the mouth tube 9 will be liftedprogressively by the water to erect the side wall 7 until the tank isfilled. Assuming that the tank is upon a level supporting surface, withthe dimensions indicated above, the tank may hold as much as twothousand five' hundred gallons of water although it will be appreciatedthat tanks with widely different capacities can be made by varying thediameters of the mouth and the base, and by varying the height of thewall. It is found that the filled tank has a remarkable degree ofstability. The mouth tube 9 is relatively rigidly supported by the waterenclosed within the tank, and an adult person can stand upon the mouthtube, using it as a platform from which to dive. It is found that thefilled tank is stable when placed on an inclined supporting surface witha gradient of up to about one in five. Whenthe tank is filled whilst itis resting upon an inclined surface, itwill be appreciated that thecapacity of the tank will be decreased.

If so desired, the tank may be filled or emptied through a pipe passingthrough the side wall thereof at a location just above the base tube.

I claim:

1. A collapsible storage tank for liquids, comprising a flexible,substantially circular base panel, a first, endless, substantiallycircularly extending inflatable tube attached to the periphery of thebase panel, a second, endless, substantially circularly extending tubeconstituting the mouth of the tank and enclosing an area smaller thanthat enclosed by said first tube, and a flexible side wall attached toand between said first and second tubes, whereby, when the tubes areinflated and liquid is introduced into the mouth, said second tubefloats upon the liquid and causes the wall to be erected, and toconverge inwardly from said first tube to said second tube.

2. A collapsible storage tank for liquids, comprising, a flexible,substantially circular base panel, a first, endless, substantiallycircularly extending inflatable tube attached to the periphery of thebase panel and formed from a plurality of straight tube sections joinedend to end, a second, endless, substantially circularly extendinginflatable tube constituting the mouth of the tank and also formed froma plurality of straight tube sections joined end to end, said secondtube enclosing an area smaller than that enclosed by said first tube,and a flexible side wall attached between said first and second tubes,whereby, when the tubes are inflated and liquid is introduced into themouth, the latter floats upon the liquid and causes the wall to beerected and to converge from said first tube to said second tube.

3. A collapsible storage tank for liquids as claimed in claim 2, whereinthe diameter of each tube is relatively large .as compared with itslength, whereby low inflation pressures may be employed.

4. A collapsible storage tank for liquids as claimed in claim 2, whereinthe side wall is constituted by a plurality of flexible panels, each ofwhich is attached at one end to a tube section of said first tube and atthe other end to a tube section of said second tube, and each of whichis broader at said one end than at said other end.

References Cited in the file of this patent UNITED STATES PATENTS ho s/

